postgres

README

PostgreSQL

Environment based configuration

Configuration for the PostgreSQL connection pool of the microservice.

• POSTGRES_PORT default: 5432
  • Port to be used for listening used if address is not specified
• POSTGRES_HOST default: localhost
  • Host where the PostgreSQL can be found (dns or IP)
• POSTGRES_PASSWORD default: pace1234!
  • password to access the database
• POSTGRES_USER default: postgres
  • postgres user to access the database
• POSTGRES_DB default: postgres
  • database to access
• POSTGRES_MAX_RETRIES default: 5
  • Maximum number of retries before giving up
• POSTGRES_RETRY_STATEMENT_TIMEOUT default: false
  • Whether to retry queries cancelled because of statement_timeout
• POSTGRES_MIN_RETRY_BACKOFF default: 250ms
  • Minimum backoff between each retry
• POSTGRES_MAX_RETRY_BACKOFF default: 4s
  • Maximum backoff between each retry
• POSTGRES_DIAL_TIMEOUT default: 5s
  • Dial timeout for establishing new connections
• POSTGRES_READ_TIMEOUT default: 30s
  • Timeout for socket reads. If reached, commands will fail with a timeout instead of blocking
• POSTGRES_WRITE_TIMEOUT default: 30s
  • Timeout for socket writes. If reached, commands will fail with a timeout instead of blocking.
• POSTGRES_POOL_SIZE default: 100
  • Maximum number of socket connections
• POSTGRES_MIN_IDLE_CONNECTIONS default: 10
  • Minimum number of idle connections which is useful when establishing new connection is slow
• POSTGRES_MAX_CONN_AGE default: 30m
  • Connection age at which client retires (closes) the connection
• POSTGRES_POOL_TIMEOUT default: 31s
  • Time for which client waits for free connection if all connections are busy before returning an error
• POSTGRES_IDLE_TIMEOUT default: 5m
  • Amount of time after which client closes idle connections
• POSTGRES_IDLE_CHECK_FREQUENCY default: 1m
  • Frequency of idle checks made by idle connections reaper
• POSTGRES_HEALTH_CHECK_TABLE_NAME default: healthcheck
  • Name of the Table that is created to try if database is writeable
• POSTGRES_HEALTH_CHECK_RESULT_TTL default: 10s
  • Amount of time to cache the last health check result

Documentation

Overview

Package postgres helps creating PostgreSQL connection pools

Index

• func ConnectionPool() *pg.DB
• func CustomConnectionPool(opts *pg.Options) *pg.DB
• type HealthCheck
  • func (h *HealthCheck) CleanUp() error
  • func (h *HealthCheck) HealthCheck() (bool, error)
  • func (h *HealthCheck) Init() error

Functions

func ConnectionPool

func ConnectionPool() *pg.DB

ConnectionPool returns a new database connection pool that is already configured with the correct credentials and instrumented with tracing and logging

func CustomConnectionPool

func CustomConnectionPool(opts *pg.Options) *pg.DB

CustomConnectionPool returns a new database connection pool that is already configured with the correct credentials and instrumented with tracing and logging using the passed options

Fot a health check for this connection a PgHealthCheck needs to be registered:

servicehealthcheck.RegisterHealthCheck(...)

Types

type HealthCheck

type HealthCheck struct {
	Pool *pg.DB
	// contains filtered or unexported fields
}

HealthCheck checks the state of a postgres connection. It must not be changed after it was registered as a health check.

func (*HealthCheck) CleanUp

func (h *HealthCheck) CleanUp() error

CleanUp drops the test table.

func (*HealthCheck) HealthCheck

func (h *HealthCheck) HealthCheck() (bool, error)

HealthCheck performs the read test on the database. If enabled, it performs a write test as well.

func (*HealthCheck) Init

func (h *HealthCheck) Init() error

Init initialises the test table